Tank cleaning system



y 1962 E. R. MILLER 3,033,215

TANK CLEANING SYSTEM Filed Dec. 4, 1959 2 Sheets-Sheet 1 FIG. 1

fg Q @I //V VE N TOR A T TOR/V5 Y May 8, 1962 E. R. MILLER TANK CLEANING SYSTEM 2 sheets sheet 2 Filed Dec. 4, 1959 b //VVEN7'0R I EL 0 R. lbw

ATTORNEY Patented May 8, 19 62 3,033,215 TANK CLEANING SYSTEM Eldon R. Miller, Iowa City, Iowa, assignor to Eldon Miller, Inc., a corporation of Iowa Filed Dec. 4, 1959, er. No. 857,355 7 Claims. (Cl. 134-98) This invention relates to tank cleaning systems and particularly to an improved apparatus for cleaning tanks which is self-contained and readily portable with the tank as part of the vehicle or tank structure.

In the transportation of commodities in tanks which may be hauled over highways by trucks, such as tank trailers, or in railway tank cars and other permanently installed tanks which are adapted to be transported from place to place, it generally is necessary and desirable that the interior of the tank be thoroughly cleaned before each reloading of the tank with another load of the same or of a different commodity. This becomes particularly important in the case of a reloading with a different commodity in order to assure against contamination by the material which was contained in the tank in its last previous load.

In many cases, a vehicle tank will be unloaded at a destination where cleaning facilities are not readily available. It then becomes necessary to haul the empty tank to a site where it properly can be cleaned before it can be taken to the place where it is to be reloaded for another trip. This entails a considerable expense and loss of time for the trip to and from the cleaning site. It is highly desirable, therefore, to be able to clean a tank immediately after it has been unloaded so that it can be reloaded with the same or a different commodity after traveling in the most direct route to the point where it is to be reloaded. Cleaning of the tank immediately after unloading also has the added advantage that small amounts of the commodity which has been unloaded, and which at times sticks to the surface of the tank as a film or otherwise, can more readily and more completely be removed immediately after the tank has been emptied than after such material has partially or completely dried.

It also is desirable that the unloading hoses, couplings, and similar connections should be cleaned between each loading of the tank, so that material passing through such connections will not be contaminated by any residue which may have been left therein from a prior load. In many instances, the point of destination for a tank load of material is not coincident with the point at which the tank is to be reloaded with material, and it would be highly desirable, from the standpoint of more effective utilization of time, to have a cleaning system which is self-contained and transportable with the tank, so that it can be utilized for cleaning of the tank and its appurtenant connections while the tank is being moved from an unloading terminal point to a loading terminal point. This can bmt be accomplished by providing means for thoroughly washing and cleaning the interior of the tank by a system which includes a suitable storage of water or similar cleaning fluid, together with storage compartments for various detergents which might be needed in order to clean different commodities from the tank and its appurtenances, with means for selectively supplying the desired detergent in the correct proportions to the cleaning fluid which is used for cleaning the tank.

According to the present invention, an improved tank cleaning system is provided which is adapted to thoroughly to clean the interior of a vehicle tank after it has been unloaded without the need of taking the tank to a cleaning terminal. The cleaning system is adapted to be transported along with the tank, preferably by having the major components assembled directly on the tank.

It is adapted to provide for cleaning the interior of the tank with hot cleaning fluid and to supply various detergents in desired proportions to the cleaning fluid in order to assure the most efiective cleaning.

When the material which is to be cleaned from the tank can properly be removed by relatively cold cleaning fluid which is available at the terminal where the tank is located, such cleaning fluid may be supplied directly to cleaning spray elements and may be drained directly through tank draining means, thus saving the expense of pumping cleaning fluid through the system. The pump and the pump connections which are conventionally provided for discharging commodities from the tank may be used for pumping the cleaning fluid out of the tank and thereby cleaning the pump and its connections as the fluid passes therethrough.

Alternatively, the pump and its connections may be connected to a cleaning fluid storage tank for pumping fresh cleaning fluid from the storage tank through the pump to a spray head in the tank to be cleaned. This latter connection of the pump and cleaning fluid storage tank makes possible the provision of an entirely selfcontained cleaning system which, together with a plu rality of detergent tanks suitably connected to the cleaning fluid supply, enables the cleaning of the tank as it is traveling between an unloading terminal point and a reloading terminal point. It also makes possible the cleaning of the tank immediately after it has been unloaded, even where it may be reloatded at the same terminal and where independent cleaning facilities are not available.

An additional important feature of the present improved cleaning system is the utilization of a separate source of motive power for driving a pump which is used for unloading the tank and for circulating cleaning fluid, so that the cleaning system may be operated entirely independently of the main source of motive power, such as the truck engine. In this manner, the large truck engine need not be operated when the vehicle is not in motion, and the smaller, more eflicient pumping engine is all that need be in operation for unloading of the tank and for circulation of the cleaning fluid. In addition, where the cleaning is done while the vehicle is in motion between terminals, the provision of a small auxiliary engine for driving the cleaning pump does not divert power from the main engine, and thereby enables the utilization of the main motive power entirely for the hauling of the vehicle.

Another important feature of the present cleaning system is the utilization of an exhaust heater arranged in the water storage tank which provides for heating the Water which is stored for cleaning of the tank by the exhaust of the auxiliary engine which drives the pump. In this manner, when the pump is being driven by the auxiliary engine while unloading the tank, the cleaning water in the water storage tang is being heated, so that, when the commodity tank has been emptied, a supply of hot cleaning water is available for immediate use.

Preferably, the present system also is provided with a generator which also is driven by the auxiliary engine, and which is connected to an electric heater, such as a conventional immersion heater, arranged within the Water storage tank to assist the exhaust heater in heating the cleaning water in the storage tank. In this manner, the cleaning water which isstored in the tank is heated in advance of the time when it is to be used for cleaning purposes. If a source of water supply is available at the point where the tank is to be cleaned while the tank is stationary, the external source of water supply may be connected directly to the water tank to replenish the cleaning water in the cleaning system, so that as the water is being used, the fresh water will be heated to a certain extent by the two heaters in the storage tank.

The basic features of this tank cleaning system will be found to be equally useful for tanks which are transported by road, rail, air, ship, or other type of vehicles.

It is an object of the present invention to provide an improved tank cleaning system.

Another object of the present invention is to provide an improved self-contained portable cleaning system for a vehicle tank.

A further object of the present invention is to provide a vehicle tank cleaning system which may be used for cleaning the tank while it is in transit between terminal points.

Still another object of this invention is to provide an improved vehicle tank cleaning system which may be connected to a separate source of water and alternately either to supply the Water directly into the conduits of the cleaning system or to supply the water to a storage tank where it may be heated before being pumped through the cleaning system.

A still further object of this invention is to provide a transportable tank cleaning system having its own source of hot water and means for heating fresh water which may be supplied to the system.

Yet another object of this invention is to provide a self-contained tank cleaning system having a plurality of storage compartments for dilferent detergents, with means for selectively supplying such detergents in desired proportions into the cleaning fluid and providing for cleaning the tank together with the discharging pump and all of the various connections through which material is passed While emptying the tank.

Further objects and advantages of this invention will become apparent from the following description referring to the accompanying drawings, and the features of novelty which characterize this invention will be pointed out with particularity in the claims appended to and forming a part of this specification.

In the drawings:

FIG. 1 is a side elevational view of a tank truck trailer provided with a cleaning system incorporating an embodiment of the present invention;

FIG. 2 is a side elevational view of the compartment housing the major operating components of the cleaning system with the covers of the compartment removed, showing the general arrangement of these components;

FIG. 3 is a fragmentary transverse sectional view through the tank and cleaning equipment compartment illustrating the arrangement of the compartment and the cleaning fluid circuating connections in relation to the tank body;

FIG. 4 is a fragmentary elevational view of the upper end of one side of the ladder secured to the tank and forming part of the conduit for conducting cleaning fluid into the tank;

FIG. 5 is an enlarged elevational view, partly in section, of the quick-coupling assembly utilized for coupling various of the fluid conduits of the cleaning system, such as that shown at the upper end of the ladder in FIGS. 1 and 4;

FIG. 6 is a side elevational view of the compartment containing the major components of the cleaning system similar to that shown in FIG. 2, with various parts broken away in order to illustrate more clearly the connections of the cleaning fluid system and the operating arrangement of the control valves in the system;

FIG. 7 is a perspective schematic view of the hydraulic flow system of the cleaning apparatus and the various control valves showing the relationship of these parts in the over-all equipment illustrated in the other figures of the drawings; and

FIG. 8 is an enlarged perspective view showing the details of valve operating cams which are utilized for selectively operating the drain valves of the tank, as shown in FIGS. 3, 6, and 7.

Referring to the drawings, an improved cleaning system for a transportable tank incorporating the present invention is shown, for illustrative purposes, applied to a truck trailer tank body. Such a trailer tank body usually is formed of a plurality of compartments, and in the illustrated construction is made of two compartments 1 and 2, Which are separated by a dividing wall 3 permanently secured around its periphery to the inner surface of the tank body. Such a truck trailer is adapted to be hauled from place to place by any suitable tractor truck and is supported adjacent the rear end thereof by suitable truck wheels 4.

Each compartment of the tank body preferably is formed with a manhole in the upper part thereof, and, in a two compartment body as illustrated, these manholes are preferably arranged closely adjacent to the dividing Wall 3 so that a single service ladder 5 can be suitably mounted, as by brackets 6, directly on the outer surface of the tank body. In order to facilitate closing of the manholes into each tank section, collars 7 are arranged around each manhole, and a suitable removable cover 8 is adapted to close these manholes. The manhole covers 8 may be removed in order to provide suitable filling openings into the tank compartments 1 and 2 and also in order to provide means of ingress and egress, if it is found necessary for a person to go into the tank for inspection or repair purposes.

In some instances, it may be found convenient to open the manholes to provide a large opening for filling of the tanks, but in most instances, it will be easier to maintain the cleanliness of the tank and the material supplied to the tank if the filling hose is connected to a quickcoupling fitting 9 suitably secured to a filling opening in each manhole cover 8. These quick-coupling fittings may be of any suitable type, such as that illustrated in detail in FIG. 5. In this construction, the fitting 9 is formed with a substantially cylindrical body 10 having a reduced diameter threaded shank or stem 11 which is adapted to be screwed into a complementary internally threaded opening in the manhole cover 8. A gasket 12 of suitable material, such as deformable synthetic rubber, is seated on an internal shoulder 13 formed at the end of the cylindrical body 10 adjacent to the reduced diameter threaded stem 11 and is fitted into a shallow groove or recess 14 formed in the end of the inner surface of the cylindrical body 10, so as to hold the gasket firmly in place to assure proper placement of the gasket and to prevent accidental displacement thereof.

Suck quick-coupling fittings are conveniently formed with a pair of ears 15 on each side thereof to which cam arms 16 are pivotally secured by pins 17 for retaining a coupling adaptor or a closure plug in the coupler fitting. Each cam arm 16 is formed with an accurately machined cam 18 which is aligned with an aperture 19 in the side of the cylindrical body 10, such that, when the arms 16 are lowered into the position shown in FIG. 5, the earns 18 project through the apertures 19 into the space within the cylindrical body 10, and when the cam arms 16 are raised, the cams 18 are pivotally swung out of the apertures 19 and do not extend into the interior of the cylindrical body 10.

Such quick-coupling fittings may be closed by a suitable plug, such as that shown in FIG. 4, which is formed with a main cylindrical body 20 having an accurately machined arcuate groove 21 extending circumferentially around the plug body 20 and spaced from the end thereof a distance such that, when the plug is inserted into the coupler body 10 and the cam arms 16 are pivoted downwardly to the positions shown in FIG. 5, the cams 18 will bias the plug snugly into fluid sealing engagement with the gasket 12. Such plugs can readily be secured against accidental loss by a suitable chain 22 extending to one of the finger rings 23 on the outer ends of the cam arms 16, as shown in FIG. 4.

A quick-coupling fitting 9, similar to that fitted into the manhole cover 8, also preferably is secured to the upper end of each tubular side post 5' of the ladder .5. During normal transportation of the tank, when the cleaning system is not in operation, a sealing plug 2% is adapted to be inserted into the coupierfitting 9 in each manhole cover 8 and at the top of each tubular ladder side post 5', so as securely to seal the openings through the coupler fittings 9 against the passage of foreign material.

As shown in FIG. 6, a quick-coupling adaptor 8 forms the other half of the coupling and is secured to the tubular member or pipe which is to be coupled through the quick-coupling fitting. In one of the conventional forms as shown in FIG. 5, this quick-coupling adaptor 8 is provided with a cylindrical body 24 which is formed with a shank or neck portion for securing the adaptor to the tubular member or pipe. The neck 25 may be formed with any suitable securing means, such as ribs or threads 26, for firmly securing the adaptor to the pipe, tube, or hose. An arcuate peripheral groove 27 is formed in the outer cylindrical surface of the adaptor body portion 24 and is spaced from the end thereof in the same manner as the groove 21 in the plug 20, so that when an adaptor 8 is inserted into a cylindrical body It) of a fitting 9 with the cam arms 16 raised from the position shown in FIG. 5, the free end 24' of the adaptor 8 will engage the outer surface of the gasket 12. The cam arms 16 then are pivotally turned away from the adaptor 8, so that the cams 18 are rotated into the apertures 13 in the sides of the coupling body It) and firmly bias the adaptor end 24' into tight sealing engagement with the adjacent surface of the gasket 12 and lock it in this position.

According to the present invention, a thorough cleaning of the interior of each tank compartment can readily be obtained by suspending a suitable spray head 23 from the manhole cover 8 into the interior of each tank compartment. The spray head 28 should have a spray nozzle system which is rotatable at least around two axes perpendicular to each other. Any suitable structure to provide such a universal flow spray pattern obtainable by such a rotation of the spray nozzles can be utilized; such, for example, as those shown in Patents 2,120,784, Howald, and 2,078,566, Fletcher. These spray heads 28 are mounted on suitable rigid tubular elements or pipes 29 which extend downwardly from the manhole covers 8 to a distance which will provide for the spraying of all the interior surfaces of the tank. It has been found that by regulating the temperature of the cleaning fluid and the use of a suitable detergent or solvent in the cleaning fluid, tanks can be very thoroughly cleaned by such a spray system if the cleaning operation is performed shortly after the tank has been emptied, and before the commodity remaining on the surfaces of the tank has had a chance to congeal, dry, or otherwise solidify in the tank.

In order to minimize the weight of the auxiliary equipment on the tank so as to allow a maximum pay load to be hauled, the ladder 5 is formed with the lower ends 5" of the tubular posts 5 connected together and to a quick-coupling fitting 30, similar to the coupling fitting shown in FIG. 5. With such a construction, if the material which has been emptied from the tank is water soluble and does not require hot water for washing it out of the tank, a suitable hose connection to a source of water supply may be coupled directly to the quick-coupling fitting 30 at the bottom of the ladder. Then, with the spray nozzles 28 in position, as shown in FIG. 1, the interior of the tank can be easily cleaned by simply turning on the water supply and allowing the water to drain from the tank sections through main tank drain valves 31 and 32 in the tank compartments 1 and 2, respec tively. If only one of the tank compartments is to be cleaned, a spray nozzle 28 and its connections through its pipe 29, quick-coupling. fitting 9, and a tubular connection 33 to the upper end of the adjacent ladder post 5 can be made, while the upper end of the other ladder post 5 is kept closed by a suitable cap 20 of the type shown in FIG. 4.

Since either of the compartments 1 or 2 of the tank may be the one which is to be cleaned, provision is made for selectively opening either valve 31 or 32, while the other valve remains closed. Provision also is made for simultaneously opening valves 31 and 32 so that both tank compartments can be drained at the same time, if both are being cleaned simultaneously. A suitable cam actuating system is provided for selectively opening and closing either of the drain valves and also for opening and cl0sing and closing them simultaneously.

The valves 31 and 32 are adapted to engage valve seats 34 and 35 for closing the drainage openings and are mounted on valve stems 36 and 37 through which the cam system operates the valves to open and closed position. These valve stems extend through valve manifold connections 38 and 39 which feed into a drainage manifold 4th, and the valves 31 and 32 are resiliently biased towards closed valve positions in engagement With their respective valve seats, in any suitable manner, as by coil springs 41 and 42. These springs are compressed between the undersides of the valve manifold connections 33 and 39 and spring seats formed on cam followers 43 and 44 on the ends of the valve stems 36 and 37 opposite to the valves 31 and 32.

Operation of the valves is conveniently obtained simply by turning a control handle 45, which is mounted on a control rod 46 extending through a general control panel 47 mounted within a suitable cabinet 48. The control rod 46 extends into a suitable gearbox 49 and is mechanically connected by suitable gearing to a cam rod 5% extending from the gearbox 49 to suitable bearings mounted in brackets 51, which are suspended from the underside of the tank body, as by being welded thereto. A pair of valve cams 52 and 53 is mounted on the cam rod 50 and is arranged in engagement with the cam followers 43 and 44 for operating the valves Til and 32, respectively.

FIG. 8 illustrates details of the configuration and arrangement of cams 52 and 53 suitable for the selective and simultaneous operation of the valves 31 and. 32. The valves are shown in this figure in the same relative positions as in FIGS. 6 and 7, wherein valve 31 is biased to its open position by cam 52 and valve 32 is biased to its closed position by its spring 42. Each of the earns 52 and 53 is formed with a quadrant having an arcuate surface between points a and b on a radius sufiicient to hold its respective valve in open position, and is formed with another quadrant of cam surface also substantially arcuate on a smaller diameter between points 0 and a, which allows for the full closure of each respective valve. A smooth curved transition surface connects the arcuate cam surfaces between points b and c and d and a to provide for the smooth opening and closing of the valves, as these transition cam surfaces engage the cam followers 43 and 44 to move the valves between closed and open positions.

In addition, as can be seen from the relative arrangement of the cams 52 and 53 in FIG. 8, the arcuate surfaces of one cam are displaced relative to the arcuate surfaces of the other cam. Thus, when the cam 52 is turned by the cam rod 50 so that the point it engages the cam follower 43, the valve 31 is in its fully open position, as shown in FIGS. 6 and 7, and the point at of the cam 53 is in engagement with the cam follower 44 of the valve 32, so that the valve 32 is biased to its closed position. In this manner, the tank compartment 1 can be drained while the tank compartment 2 remains closed.

If it is desired to drain compartment 2 of the tank while maintaining compartment 1 closed, the control han dle 45 is turned clockwise from the position shown in the drawings. Such turning of the handle 45 will first cause the cam surface of cam 52 between points a and d to engage cam follower 43, so as to close valve 31, while the arcuate cam surface between points d and c of cam 53 engages the cam follower 44, thereby permitting the valve 32 to remain closed. Thus, when the handle 45 has been turned clockwise through 90", point at of cam 52 will be in engagement with cam follower 43 and point c of cam 53 will be in engagement with cam follower 44, so that both of the valves will be closed concurrently in this position. Further clockwise turning of the control handle 45 will cause the cam follower 43 to ride over the short radius arcuate surface of the cam 52, so that the valve 31 will remain in closed position, while such turning will cause the cam follower 44 to travel over the transition surface of cam 53 between points and b, thus raising the cam follower 44 and opening valve 32. In this manner, valve 32 has been selectively opened for the drainage of tank compartment 2, while valve 31 has been kept closed.

During normal transportation of commodities in both compartments of the tank and when it may be desired to spray the interior of the tank and allow a certain amount of the cleaning fluid to settle in the bottom of the tank, both valves 31 and 32 are closed. As has been explained, such concurrent closing of both valves is obtained when the cam followers 43 and 44 are in engagement with points d and c of cams 52 and 53, respectively.

In certain instances, it may be desired to drain both compartments of the tank simultaneously. This can be done by simultaneously opening both valves 31 and 32 by turning the control handle 45 counterclockwise 90 from the position shown in FIGS. 6, 7, and 8 when valve 31 is open and valve 32 is closed, or by turning it clockwise 90 from the position when valve 32 is open and valve 31 is closed. Either of these 90 turns will place point b of cam 52 in engagement with cam follower 43, thereby opening valve 31 and place point a of cam 53 in engagement with cam follower 44, so as to open valve 32. Obviously, other suitable valve control arrangements can be devised for selectively and simultaneously operating the valves to open and closed positions, and other camming arrangements can be readily devised for the control of more than two valves where more than two tank compartments are utilized. The foregoing valve operating arrangement is merely illustrative of a simple combination for obtaining the desired results.

This selective and simultaneous tank drain valve control also is adapted to be utilized for the selective or simultaneous emptying of commodities transported in the two sections of the tank. When emptying commodities from the tank, the commodity may be simply drained out of the tank by gravity when it is to be delivered to a point lower than the bottom of the tank, or the commodity may have to be pumped out of the tank when it is to be delivered to a point higher than the tank. In order to provide for either of these methods of delivering commodities from the tank, a dual valved delivery control is provided, so that natural gravity drainage can be utilized where this is practical, thus saving the expense of pumping the commodity from the tank and minimizing wear on the equipment. A suitable pump 54 also is connected in the delivery system for pumping material out of the tank and adapted to be driven by a small auxiliary engine 55 through suitable change speed gearing controlled by a gearshift lever 56 and a clutch controlled by a clutch lever 57.

The selection of the delivery of fluid from the tank by gravity drainage or by being pumped from the tank through the pump 54 is obtained through a set of selective valves which connect the drainage manifold 40 to either a suitable gravity drain pipe 58 or to the pump 54. This set of selective valves is adapted to be conveniently operated by a suitable handle 59 mounted on the front of the main control panel 47 and connected to suitable valves through a control rod 60 of the push-pull type. Preferably these selective valves are arranged on the outlet side of the manifold 40 so as to minimize the number of valves required; and, as shown in FIG. 7, these may comprise valves 61 and 62 which are connected between the manifold outlet 63 and respectively to the gravity drainpipe 58 and the pump 54 through a pipe connection 64. The control rod 60 operates the valves 61 and 62 through a rocker arm 65 to which it is connected through a pivot joint 66. The rocker arm is 'pivotally mounted by a pin 67 on a suitable supporting bracket 68 which is rigidly secured to the valve housing for the valves 61 and 62. In addition, the rocker arm 65 is connected to the valves 61 and 62 through branches 69 and 70 which actuate valve stems 71 and 72 connected to the valves 61 and 62, respectively, through pivotal connections of the ends of the branches 69 and 70 to the ends of the valve stems 71 and 72.

With such an arrangement, the tank can be drained by gravity by pulling on the handle 59, so that the rocker arm 65 is swung in a counterclockwise direction, as viewed in FIG. 7, thereby turning the branches 69 and 70 in a counterclockwise direction, so as to push the valve stem 72 towards the manifold outlet 63 to close the valve 62 thereby closing off the connection of the manifold outlet 63 to the pump pipe connection 64. This same counterclockwise rotation of the rocker arm branches 69 and 70 pulls the valve stem 71 away from the manifold outlet, so as to open valve 61 and to connect the manifold outlet to the gravity drain pipe 58.

If it is desired to empty the tank through the pump 54, the valve handle 59 is pushed inwardly towards the control panel 47, thereby rocking the rocker arm 65 in a clockwise direction as viewed in FIG. 7. This turns the branches 69 and 70 in a clockwise direction, so that the branch 69 pushes the valve stem 71 towards the manifold outlet 63 and closes valve 61, thereby closing the connection between the manifold outlet and the gravity drainpipe 58. Simultaneously, the rocker arm branch 70 draws the valve stem 72 away from the manifold outlet 63, thereby opening valve 62 and providing a connection between the manifold outlet 63 and the pump 54 through the pipe connection 64. In this manner either tank compartment may be selectively emptied, or both may be emptied simultaneously, and the material which is emptied may either be drained by gravity or be pumped through the pump 54.

Under most circumstances, it would be found desirable to clean the tank compartments with a warm water solution. This can readily be provided by pumping relatively warm water with a suitable detergent through the tubular ladder posts 5' to the spray heads 28. In order to assure the availability of cleaning water for cleaning the tank compartments as soon as possible after these compartments have been emptied of commodities, the present cleaning system includes a water storage tank 73 which is conveniently arranged in the cabinet 48 adjacent to the auxiliary engine 55. This arrangement makes possible the cleaning of the tank compartments even if a source of clean water supply is not available at the point of delivery of the commodity from the tank. In addition, an exhaust heater 74 is arranged in the water storage tank 73 and connected to the exhaust manifold of the auxiliary engine 55. Exhaust gases passing through the exhaust heater 74 from the engine can be suitably exhausted to atmosphere through an exhaust pipe 75. In this manner, heat in the exhaust gases of the auxiliary engine will be utilized to heat the water in the storage tank 73, thereby providing a more efiicient utilization of the fuel required to operate the cleaning system. This will be particularly useful where the commodity from the tank compartments 1 and 2 is delivered through the pump 54, as the exhaust gases passing through the exhaust heater 74 during the emptying of the commodity from the tank compartments will be heated by the exhaust gases of the engine 55 as it drives the pump 54 to empty the commodity. The water in the storage tank 73 will thus be thoroughly heated and ready to use for cleaning the tank compartments as soon as the compartments have been emptied.

At times, it may be found that the exhaust heater 74 will not adequately heat the Water in the water storage tank 73 during the emptying of a commodity from the tank compartments and, therefore, an auxiliary electric heater may be provided for further heating of the water inthe tank 73. This electric heater preferably is, in the form of a conventional immersion electric ,heater 76 which is mounted so thatthe heating element extends directly into thetank 73.. The, electric heater 76 is conveniently energized by being connected to a generator 77, which may be driven in any suitable manner, as by belts 78, froma pulley 79 on a drive shaft 80 which connects the auxiliary engine 55 to the pump 54 through a clutch and suitable gearing.

Water from-the storage tank 73 is adapted to be supplied into the cleaning system through a pipe connection 78 and a suitable shut-off valve79, such as a conventional manual valve, which functions to control the flow of water from the tank 73 to the pump inlet pipe 64; In order to pump water from the tank .73 into the, cleaning system, it is essential that the valve 62 be closed unless it is desired to recirculate some of the used cleaning fluid which is being drained from the tank. With thevalve 62 in closed position, the water receive-d from the pipe 64 is pumped by the pump 54 through a suitable hose 80 into the tubular posts 5 of the ladder 5.. This hose 80 may conveniently comprise the delivery hose through which material has been pumped from the main tank, so that the passage of cleaning water through the hose 80 will' not only provide the connection of the pump to the tubular ladder posts, but also will provide for simultaneously cleaning the inside of the hose. Both ends of the hose 80 preferably are formed with quick-coupling connectors of any conventional type, such as those shown in FIG. 5, so that the hose can be quickly connected and disconnected from the pump by a pump coupling fitting 9' and a similar coupling fitting 30 at the base of the tubular ladder posts 5. If no recirculation of the cleaning fluid is desired, the valve 62 is kept closed and the valve 61 is opened, so that the used cleaning fluid 'will'be drained through the manifold outlet 63, the valve 61, and the gravity drainpipe 58.

As is best shown in FIG. 7, aplurality of detergent- 73 to the spray heads 28 by being pumped into the cleaning system by the pump 54 when the valve 73 is opened.

If the material which is to be cleaned from the tank requires a particular type of detergent in the cleaning fluid for suitably cleaning .the tank, the detergent may be -selected from any of the tanks 81, 82, and 83 by opening the proper valve 87, 88, or 89, or two or more of these valves if a mixture of detergents is desired. This provides for the supply of detergent from one or more of the detergent tanks directly into the fluid passing.- through the tubular ladder posts 5', such that the flow of water through these-ladder posts draws the detergent from thesupply pipe 90 .andmixes it withtheflow of water so that it is thoroughly .mixed as it .is sprayed into. the tank by the.

spray heads 28. If only one compartment of the tank is to be cleaned, only one spray head is connected to one of the ladder posts 5, and the closure plug 20 is left in the top of the other ladder post 5'. The provision of individual shut-01f valves 87, 88, and 89 for each of the detergent tanks also advantageously provides for controlling the rate of flow of detergent from each detergent tank according to the amount of opening of each respective shut-off valve 87, 88, and 89.

Furthermore, in most instances, it will be desirable to rinse the compartments 1 and 2 of the tank after they have been thoroughly cleaned by cleaning fluid containing detergent, and this can easily be done simply by shuttubular ladder posts 5 to the spray nozzles.28,..and be drained directly from-the tanks through the valve 61 and the gravity drainpipe 58.-

In this manner, a very efiicient and versatile cleaning I system is provided which can be used to clean one or. all compartmentsof the tank either While the tank is stationary or while it is being transported fromone location to another, and the power required for operating the cleaning system in no way affects or is controlled by the main source of motive power which is used for transporting the tank. In addition, the system utilizes the heat generated by the auxiliary engine 5 both .for driving the auxiliary equipment, suchas .thepump, 54 and the generator 77,and also very effectively utilizes exhaust heat for :heating the cleaning Water in the water storage tank 73.

While a particular embodiment of this invention has been illustrated and described,modifications-thereof will occur to those skilled in the art. It is to'be understood, therefore,,that this invention is not to be limited to the particular details disclosed, and it is intended in the appended claims to cover all'modifications within the spirit a and scope of this invention.

I claim:

1. A cleaning system for a tank, comprising a cleaning fluid supply means, means including a spray. nozzle adapted to be in said tank, means including a ladder having hollow side posts mounted on the side of said vehicle tank body for conducting cleaning fluid to'said spray nozzle from said fluid supply means, means for conducting fluid from the-upper end of one of said ladder posts to said spray nozzle and means for connecting saidfluid supply means to the lower ends of said ladderpostsn 2. A cleaning system for a tank with a tank filling opening and aremovablecover'thereon, comprising a cleaning fluid supply means, means-including a spray nozzle insertable through the tank opening into-the tank, means including a ladder having hollow. side posts mounted on the side of said vehicle tank body for con-.- ducting cleaning fluid to said spray nozzle fromsaid fluid supply means, readily disconnectable means for conduct-. ing fluid from the upper end of one of said ladder posts to said spray nozzle, means for connecting said fluid; supply means to the lower ends of said ladder posts, a plurality of detergent containers, means connected to each" of said ladder posts for conducting detergent fI01'l'lf63Chf,- ofsaid containers to said posts,-'-means for selectively opening and closingofl passage of detergent from eacludeterg ent, container .to;;said fluid conducting;means providing. for the supply of detergent to said fluid conducting-means; from said detergentzcontainers, and means for; draining said tank:

3. A cleaning system-:for a tank body havinga plurality of sections each with-a tank. fil-ling opening;.and a re--.

movable cover --there0n-,= comprising a cleaningzfluidsupaw ply means includinga-water storage tank, a pump, an: engine for'driving said pump, means includingan-iexhaustx heater connected to the exhaust of said engine and arranged to heat said water storage tank, means for connecting said storage tank to said pump, means including a spray nozzle insertable through the filling opening into each of said tank sections, means including a ladder having hollow side posts mounted on the side of said vehicle tank body for conducting cleaning fluid to each of said spray nozzles from said fluid supply means, readily disconnectable means for conducting fluid from the upper ends of said ladder posts to said spray nozzles, readily disconnectable means for conducting fluid to the lower ends of said ladder posts from said pump comprising a hose adapted to be used alternatively for delivery of a 1 1 commodity from the vehicle tank body by said pump to a receiving container, a drain valve in each section of said tank body, means for opening and closing each of said drain valves selectively and concurrently, a gravity drain, and means for selectively connecting said drain valves to said gravity drain and to said pump.

4. A cleaning system for a tank body having a plurality of sections each with manhole tank filling opening and a removable cover thereon, comprising a cleaning fluid supply means including a water storage tank, a pump, a source of electric power comprising a generator driven by said engine, means including an electric water heater energized by said generator and arranged to heat said water storage tank, means for connecting said storage tank to said pump, means including a spray nozzle insertable through the filling opening into each of said tank sections, means including a ladder having hollow side posts mounted on the side of said vehicle tank body for conducting cleaning fluid to each of said spray nozzles from said fluid supply means, readily disconnectable means for conducting fluid from the upper ends of said ladder posts to said spray nozzles, readily disconnectable means for conducting fluid to the lower ends of said ladder posts from said pump comprising a hose adapted to be used alternatively for delivery of a commodity from the vehicle tank body to a receiving container, a drain valve in each section of said tank body, means for opening and closing each of said drain valves selectively and concurrently, a gravity drain, and means for selectively connecting said drain valves to said gravity drain and to said pump.

5. A cleaning system for a vehicle tank with a tank filling opening, comprising a cleaning fluid supply means, means including a spray nozzle insertable through the filling opening into said tank, means including a ladder having hollow side posts mounted on the side of said vehicle tank body for conducting cleaning fluid to said spray nozzle from said fluid supply means, readily disconnectable means for conducting fluid from the upper' end of one of said ladder posts to said spray nozzle, readily disconnectable means for connecting said fluid supply means to the lower ends of said ladder posts, a plurality of detergent containers, means connected to each of said ladder posts for conducting detergent from each of said containers to said posts, means for selectively opening and closing otf passage of detergent from each detergent container to said fluid conducting means providing for the supply of detergent to said fluid conducting means from said detergent containers, and means for draining said tank.

6. A cleaning system for a vehicle tank body having a plurality of sections each with a tank filling opening, comprising a cleaning fluid supply means including a water storage tank, a pump, means for connecting said storage tank to said pump, means including a spray nozzle insertable through the filling opening into each of said tank sections, means including a ladder having hollow side posts mounted on the side of said vehicle tank body for conducting cleaning fluid to each of said spray nozzles from said fluid supply means, readily disconnectable means for conducting fluid from the upper ends of said 12 ladder posts to said spray nozzles, readily disconnectable means for conducting fluid to the lower ends of said ladder posts from said pump comprising a hose adapted to be used alternatively for delivery of a commodity from the vehicle tank body by said pump to a receiving container, a plurality of detergent containers, means connected to each of said ladder posts for conducting detergent from each of said containers to said fluid conducting means leading to each of said spray nozzles, means for individually opening and closing off passage of detergent from each detergent container to said fluid conducting means providing for the supply of detergent to said fluid conducting means from one or more of said detergent containers, a drain valve in each section of said tank body, means including operating cams for selectively opening and closing each of said drain valves separately and concurrently, a gravity drain, and means including discharge valves for selectively connecting said drain valves to said gravity drain and to said pump.

7. A cleaning system for a tank body having a plurality of sections each with a manhole tank filling opening and a removable cover thereon, comprising a cleaning fluid supply means including a water storage tank, a pump, an engine for driving said pump, means including an exhaust heater connected to the exhaust of said engine and arranged to heat said water storage tank, a source of electric power comprising a generator driven by said engine, means including an electric water heater energized by said generator and arranged to heat said water storage tank, means for connecting said storage tank to said pump, means including a spray nozzle insertable through the filling opening into each of said tank sections, means including a ladder having hollow side posts mounted on the side of said vehicle tank body for conducting cleaning fluid to each of said spray nozzles from said fluid supply means, readily disconnectable means for conducting fluid from the upper ends of said ladder posts to said spray nozzles, readily disconnectable means for conducting fluid to the lower ends of said ladder posts from said pump comprising a hose adapted to be used alternatively for delivery of a commodity from the vehicle tank body by said pump to a receiving container, a plurality of detergent containers, means connected to each of said ladder posts for conducting detergent from each of said containers to said fluid conducting means leading to each of said spray nozzles, means for individually opening and closing off passage of detergent from each detergent container to said fluid conducting means providing for the supply of a detergent from one or more of said detergent containers, a drain valve in each section of said tank body, means for opening and closing each of'said drain valves selectively and concurrently, a gravity drain, and means for selectively connecting said drain valves to said gravity drain and to said pump.

References Cited in the file of this patent UNITED STATES PATENTS 2,045,752 Butterworth June 30, 1936 2,648,342 Vani Aug. 11, 1953 2,933,093 Handyslide Apr. 19, 1960 

